Rievtech EXM-12DC-DA-R-HMI, User Manual

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When a high level in En, the Modbus Read Write block will be activated and the x-Messenger could
communicate with peripheral as a master via RS232 , RS485 or Ethernet interface you selected, further the
output will be switched on when the communication is established successfully. Otherwise the output (Q pin)
is keep off it means communication is failed.
A signal at input R resets output Q and disable this block at the same time
Note:
If you are using old Ethernet CPU(need deviceManger to configure the modem) without web server built-in
and you need use MODBUS through Ethernet port, then you still use MODBUS READ or MODBUS WRITE block.
The MODBUS READ WRITE( Ethernet comm type) is only for the new version Ethernet CPU.
Connection Description
Input En A high signal at En input will enable “Modbus Write” function block to be activated
Input R Reset the value read from peripheral and set the output to 0 via the R (Reset) input.
Reset has priority over En
Parameter Slave address: 1 is default .
Communication protocol: Modbus(RTU), Modbus TCP
Communication parameter: baud rate(BPS),Data bits, Stop bits,
Parity
，
Overtime(response timeout)
Comm Type: Ethernet, RS232 or RS485( Communication interface of PLC )
Data register Index: High Low /Low High
Command: 01 Read coils
02 Read Discrete input
03 Read Holding Registers
04 Read Input Registers
15 Write Multiple Coils
16 Write Multiple Registers
Register start address, count.
Output Q Q is set or reset depending on the communication status.
Successful communication , Q=1;
Failed communication ,Q=0;
Regarding of the RS232/RS485 comm type, you can refer to the instructions of Modbus read or Modbus Write